Los dátiles, un escudo frente a patologías oculares

La riqueza nutricional de los dátiles propició que en la Antigüedad se les llegara a catalogar como la fruta del «árbol de la vida». Aunque por su consistencia y aspecto se les haya hecho un hueco dentro de las frutas desecadas, lo cierto es que no se seca después de su recolección, sino antes al sol. Para Elena Gascón, dietista-nutricionista del Instituto de Ciencias de la Alimentación de la Universidad de Navarra, «aportan mayor cantidad de energía que las variedades frescas. Son una fuente importante de hidratos de carbono y fibra, por lo que ayudan a controlar el tránsito intestinal y están recomendados en casos de estreñimiento».

Dentro de los minerales, los dátiles destacan por su riqueza en potasio y magnesio. «El primero, en sinergia con la niacina o vitamina B3, favorece el buen funcionamiento nervioso y muscular, promoviendo una buena coordinación psicomotora. El magnesio se relaciona con el funcionamiento del intestino, nervios y músculos, forma parte de huesos y dientes, mejora la inmunidad y posee un suave efecto laxante», aclara Gascón. Pero todavía hay más. Dos pigmentos naturales, los betacarotenos y la luteína, continúa la experta, «ayudan a cuidar la vista y previenen enfermedades degenerativas de los ojos».

-Demasiadas calorías

Pese a todo, los dátiles contienen un valor energético nada despreciable. Hasta 279 calorías por cien gramos. Según el doctor Vicente Orós Espinosa, miembro del Grupo de Nutrición de la Sociedad Española de Médicos de Atención Primaria (Semergen), «representan un recurso excelente para reponerse de grandes esfuerzos y están especialmente indicados en la práctica de deportes de larga duración y condiciones extremas como montañismo, alpinismo o escalada, entre otros». Sin embargo, «debido a su contenido en hidratos de carbono, estarán contraindicados en personas obesas y con sobrepeso, así como diabéticos y aquellas que padezcan hipertrigliceridemia por su concentración en azúcares simples. Además, tan sólo poseen un 15 por ciento de agua, por lo que el contenido de los restantes nutrientes está aumentado», advierte Gascón.

Además, su ingesta habitual, continúa la experta, no sólo «favorece la aparición de caries dental si no se tiene una correcta higiene bucal, sino que también pueden resultar algo indigestos en personas con problemas digestivos». Entre los dátiles más populares encabeza la lista el tunecido «Deglet Noor» de piel lisa y brillante, seguido del «Medjool» con una textura arrugada y similar a un caramelo toffee. Dentro de los secos están los blandos, duros, rojos, negros y amarillos. Aunque proceden de Oriente Medio, los de Elche (Alicante) cuentan con el reconocimiento a nivel mundial.

**Publicado en "LA RAZON"

Los niños que ven mucha tv, más propensos a enfermedades cardiacas

La investigación señala que el impacto a la salud de cada hora frente a la televisión equivale a un aumento de unos 10 mm HG (milímetros de mercurio) en la presión sistólica sanguínea, de acuerdo al portal de divulgación de información científica Sciencealert. La jefa de este estudio, Bamini Gopinath, dijo que "los factores vinculados a una vida poco saludable pueden tener un impacto en la microcirculación en los primeros años de vida y aumentar el riesgo de desarrollar después problemas cardíacos y presión alta".

Los expertos del Centro de Investigación de la Visión de la Universidad de Sídney examinaron a unos 1.500 niños de seis a siete años y notaron que las arteriolas retinianas de aquellos que pasan mucho tiempo frente a la televisión son más estrechas que lo normal. Los niños que participaron en el estudio estaban expuestos un promedio de 1,9 horas al día frente a la televisión y dedicaban 36 minutos a la actividad física.

Según la investigación los niños que invertían más una hora de actividad física cada día tenían arteriolas retinianas saludables, debido a que la actividad aumenta el flujo sanguíneo y tiene un efecto positivo en los tejidos de los vasos sanguíneos. El estrechamiento de las arteriolas retinianas se asocia con hipertensión arterial, pero este estudio muestra por primera vez la relación entre una vida sedentaria durante la infancia y dicha condición.

**Agencias

Electronic medical records speed genetic health studies

Recruiting thousands of patients to collect health data for genetic clues to disease is expensive and time consuming. But that arduous process of collecting data for genetic studies could be faster and cheaper by instead mining patient data that already exists in electronic medical records, according to new Northwestern Medicine research. In the study, researchers were able to cull patient information in electronic medical records from routine doctors' visits at five national sites that all used different brands of medical record software. The information allowed researchers to accurately identify patients with five kinds of diseases or health conditions – type 2 diabetes, dementia, peripheral arterial disease, cataracts and cardiac conduction.
"The hard part of doing genetic studies has been identifying enough people to get meaningful results," said lead investigator Abel Kho, M.D., an assistant professor of medicine at Northwestern University Feinberg School of Medicine and a physician at Northwestern Memorial Hospital. "Now we've shown you can do it using data that's already been collected in electronic medical records and can rapidly generate large groups of patients."
The paper will be published April 20 in Science Translational Medicine.
To identify the diseases, Kho and colleagues searched the records using a series of criteria such as medications, diagnoses and laboratory tests. They then tested their results against the gold standard – review by physicians. The physicians confirmed the results, Kho said. The electronic health records allowed researchers to identify patients' diseases with 73 to 98 percent accuracy.
The researchers also were able to reproduce previous genetic findings from prospective studies using the electronic medical records. The five institutions that participated in the study collected genetic samples for research. Patients agreed to the use of their records for studies.
Sequencing individuals' genomes is becoming faster and cheaper. It soon may be possible to include patients' genomes in their medical records, Kho noted. This would create a bountiful resource for genetic research.
"With permission from patients, you could search electronic health records at not just five sites but 25 or 100 different sites and identify 10,000 or 100,000 patients with diabetes, for example," Kho said.
The larger the group of patients for genetic studies, the better the ability to detect rarer affects of the genes and the more detailed genetic sequences that cause a person to develop a disease.
The study also showed across-the-board weaknesses in institutions' electronic medical records. The institutions didn't do a good job of capturing race and ethnicity, smoking status and family history, all which are important areas of study, Kho said. "It shows we need to focus our efforts to use electronic medical records more meaningfully," he added.

**Source: Northwestern University

Los alimentos protectores del corazón

Alimentos protectores del corazón. Una de las principales causas de muerte son las enfermedades cardiovasculares ; por ello es importante que incluyas en tu dieta ciertos alimentos beneficiosos para tu corazón y tu sistema cardiocirculatorio.
La avena es rica en ácidos grasos omega 3, acido fólico y potasio; es muy rica en fibra y ayuda a bajar los niveles de LDL o colesterol malo evitando que las arterias se taponen. Los copos de avena con un lácteo, unos frutos rojos y una o dos piezas de fruta constituyen una opción sana y equilibrada de desayuno para todas las edades.

El salmón es un alimento rico en ácidos grasos omega 3, ayuda a reducir la presión arterial y cuidar las arterias; es recomendable consumirlo al menos dos veces por semana, para reducir el riesgo de infarto; también puedes elegir sardinas o atún.
El aguacate aporta ácidos grasos insaturados y contribuye a disminuir el colesterol malo y aumentar el colesterol bueno, el aceite de oliva es una grasa saludable, por lo que reduce el riesgo de padecer enfermedades cardiovasculares, al igual que las nueces, que puedes consumirlas unas tres o cuatro veces por semana junto con otros frutos secos, siempre crudos, sin tostar ni sal.
Las legumbres, como las habas, lentejas, alubias o garbanzos son alimentos ricos en fibra soluble y calcio, que aportan carbohidratos y proteínas vegetales, además de vitaminas y minerales. Cabe citar entre las legumbres, la soja, que es rica en fitoestrógenos y ayuda a mantener los niveles de colesterol malo o LDL bajo y aumentar el colesterol bueno o HDL, por lo que puedes consumirla con regularidad También el tofu, derivado de la soja, resulta beneficioso para el aparato cardiovascular.

**FEC( Fundación Española del Corazón )

Prenatal exposure to common insecticide linked to decreases in cognitive functioning at age 7

Researchers from the Columbia Center for Children's Environmental Health at the Mailman School of Public Health report evidence of a link between prenatal exposure to the insecticide chlorpyrifos and deficits in IQ and working memory at age seven. This is the first study to evaluate the neurotoxicity of prenatal chlorpyrifos exposure on cognitive development at the time of school entry. Findings are online in Environmental Health Perspectives. Until banned for indoor residential use by the U.S. Environmental Protection Agency in 2001, chlorpyrifos, an organophosphate pesticide, was one of the most widely used insecticides for residential pest control. In a sample of 265 New York City minority children, born prior to the ban, the researchers found evidence that increases in the amount of chlorpyrifos in the babies' umbilical cord blood were associated with decreases in performance on a measure of cognitive functioning at age 7. Specifically, higher prenatal exposure was associated with lower scores on two different scales of the Wechsler Intelligence Scales for Children (WISC-IV). On average, for each standard deviation increase in chlorpyrifos exposure, the full-Scale IQ was reduced by 1.4% (0.94 to 1.8 points) and Working Memory was reduced by 2.8% (1.6 to 3.7 points). This means that those children who have exposures in the upper 25% of the exposure distribution will score, on average, 5.5% (or 5.3 points) lower on the test of Working memory, and 2.7% (or 2.7) points lower on Full-scale IQ, as compared to those children in the lowest quartile. Furthermore, the decline in test scores begins at the lowest exposures and continues downward with increasing exposure levels. This suggests no evidence of a threshold, below which exposures are completely safe.
The Columbia researchers had previously reported that, prior to the ban, chlorpyrifos was detected in 100% of personal and indoor air samples, and 70% of umbilical cord blood collected from babies. They also reported that the amount of chlorpyrifos in babies' blood was associated with neurodevelopmental problems at age three. The new findings suggest that the relationship between prenatal chlorpyrifos exposure and neurodevelopmental deficits among cohort children persists through age seven, with possible longer-term educational implications.
"These observed deficits in cognitive functioning at 7 years of age could have implications for school performance," noted Virginia Rauh, ScD, deputy director of the Columbia Center for Children's Environmental Health (CCCEH), and lead author of the study. "Working memory problems may interfere with reading comprehension, learning and academic achievement, even if general intelligence remains in the normal range."
The good news, reports Robin Whyatt, DrPH, senior author on the paper, is that since the EPA ban took effect, exposure to the organophosphate has measurably declined. CCCEH scientists have found a 3-fold decrease in chlorpyrifos levels in personal and indoor air samples in the cohort and a more than 5-fold decrease in blood levels.
"However, agricultural use of chlorpyrifos is still permitted in the U.S.," says Dr. Whyatt, professor of Clinical Environmental Health Sciences and deputy director of CCCEH. "It is vitally important that we continue to monitor the levels of exposure in potentially vulnerable populations, especially in pregnant women in agricultural communities, as their infants may continue to be at risk."
Also published in Environmental Health Perspectives today, two other NIEHS/EPA funded Children's Environmental Health Centers present independent investigations of organophosphate pesticides and neurodevelopment. Although findings cannot be directly compared, these studies also found early cognitive and behavioral effects associated with prenatal organophosphate exposure.

**Source: Columbia University's Mailman School of Public Health

The Long-Term Effects of In Utero Exposures — The DES Story

It has been 40 years since the Journal published a seminal article by Herbst et al. (1971;284:878-81) noting the association of in utero exposure to a synthetic nonsteroidal estrogen, diethylstilbestrol (DES), and the development of a rare clear-cell adenocarcinoma (CCA) of the vagina in young women 15 to 22 years later. The identification of an in utero exposure that caused alterations to the anatomical and histologic structure of the female genital tract, infertility, and malignant transformation has changed medical thinking about both the embryologic development of the genital tract and the mechanism of carcinogenesis.
DES was developed in 1938 and used widely, including as a supplement to cattle feed in the 1960s and in humans for symptom relief from estrogen-deficiency states, postpartum lactation suppression, and treatment of prostate and breast cancer. Despite some evidence to the contrary, a 1948 study suggested that DES taken in early pregnancy prevented miscarriage.1 Over the subsequent two decades, and despite mounting evidence of lack of efficacy, DES was commonly prescribed for that purpose. Ultimately, however, it was acknowledged to be ineffective in the prevention of miscarriage. The exact number of offspring exposed to DES in utero is unknown but is thought to be several million.
The Registry for Research on Hormonal Transplacental Carcinogenesis had collected information on 431 cases of vaginal CCA by 1994. A 2007 analysis of lifetime risks of CCA reported a total of 143 cases per 97,831 person-years among women exposed to DES in utero.2 Estimates of CCA incidence among DES-exposed women range from 1 in 1000 to 1 in 10,000. Unlike the previously rare CCA that was found in postmenopausal women, CCA in DES-exposed women occurred at a median age of 19 years (range, 15 to 29 years). The registries also identified another cohort of young women — accounting for 20% of the total registry population — who were given that diagnosis during the same era but had no known history of DES exposure. This finding has led to conjectures that some of the mothers of women with CCA might have been exposed to DES through dietary sources.
The mechanism of carcinogenesis has been linked to aberrant embryologic development of the Müllerian ducts after exposure to DES. Chemicals that affect human fetal development are now called endocrine-disrupting chemicals, and an understanding of the changes caused by DES, the prototypical endocrine disruptor, has led to the identification of genetic pathways that govern the development of the reproductive tract. At a crucial developmental window in utero, DES exposure disorganizes uterine muscle layers; prevents vaginal epithelial stratification and the resorption of vaginal glands, causing vaginal adenosis; and leads to loss of the uterotubal junction. The anomalies of the reproductive tract are thought to be attributable in part to estrogen's ability to alter stromal epithelial interactions. In the past decade, DES-induced alterations of the expression of the Hox and Wnt gene families, which are involved in the patterning of the reproductive tract, have been identified. The fact that the incidence of CCA peaked during the teen years suggests that the hormonal changes of menarche triggered malignant transformation in vaginal adenosis.
For the women who were exposed to DES in utero, it meant being subjected to the trauma of multiple pelvic examinations with colposcopy and repeated biopsies, as well as living with the fear of developing cancer. Small, T-shaped uteri and other uterotubal anomalies that made it impossible to accommodate a growing fetus caused many of these women to have miscarriages — which occurred at twice the rate found among their non–DES-exposed contemporaries. Some sons of women who were given DES have also been reported to have epididymal cysts, microphallus, cryptorchidism, or testicular hypoplasia. The enormous health care costs for this cohort and the disruptions of their lives cannot be fully measured; in some cases, these effects have been devastating.
The lessons learned from the DES story are powerful. Endocrine disruptors may cause alterations in the reproductive tract that have severe consequences and form the basis of disease in adults decades later. Endocrine disruptors may come not only from ingested medicines, but potentially also from the environment through food. It is very difficult to recognize a teratogenic consequence of a prenatal exposure when the malformation does not manifest until 20 years later.
There continue to be unanswered questions about the cohort of DES-exposed offspring. Will they encounter other unique health problems as they age? A slight increase in the rate of breast cancer among DES-exposed women over 40 years of age has been reported, but there has been no increase in other gynecologic cancers. Are the children of DES-exposed people at higher risk for genetic changes and disease? Epigenetic changes have been seen in studies in animals. However, a 2008 study of the third generation — the grandchildren of women who were given DES during pregnancy — did not uncover an increased risk of disease in humans.5
Ultimately, the DES story humbles us. It serves as a reminder that though the narrow lens of today might reassure us that an intervention is safe, it is only with the wisdom of time that the full consequences of our actions are revealed.

*Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.
This article (10.1056/NEJMp1104409) was published on April 20, 2011, at NEJM.org.

*Source Information
Drs. Goodman and Schorge are associate professors, and Dr. Greene is a professor, of obstetrics, gynecology, and reproductive biology at Harvard Medical School and Massachusetts General Hospital — both in Boston; Dr. Greene is also an associate editor of the Journal.

Kids' 'screen time' linked to early markers for cardiovascular disease

Six-year-olds who spent the most time watching television, using a computer or playing video games had narrower arteries in the back of their eyes — a marker of future cardiovascular risk, in a first-of-its-kind study reported in Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association. Australian researchers found that more sedentary behavior such as "screen time" was associated with an average narrowing of 2.3 microns in the retinal arteriolar caliber. A micron is one thousandth of a millimeter or one-25th of a thousandth of an inch.
In the study, 6- to 7-year-olds who regularly participated in outdoor physical activity had 2.2 microns wider average retinal arteriolar compared to those children with the lowest level of activity.
The magnitude of the narrowing associated with each hour of television/computer viewing was similar to that associated with 10 millimeters of mercury (mm HG) increase in systolic blood pressure in children, researchers said.
"We found that children with a high level of physical activity had a more beneficial microvascular profile compared to those with the lowest levels of physical activity," said Bamini Gopinath, Ph.D., lead author and senior research fellow at the Center for Vision Research at the University of Sydney. "This suggests that unhealthy lifestyle factors may influence microcirculation early in life and increase the risk of cardiovascular disease and hypertension later in life."
Retinal microvascular caliber is a marker for cardiovascular disease and high blood pressure in adults. But this is the first time that a sedentary lifestyle in childhood showed a narrowing of the vessels in the retina that could be a subclinical marker for cardiovascular disease in the future.
The study included 1,492 children in 34 primary schools in Sydney, Australia. Parents answered a 193-item questionnaire, providing the number of hours spent each week in indoor and outdoor physical activity and sedentary activity such as watching television, videogames, computer time and reading.
Researchers took digital photographs of the vasculature in the back of each child's eye, then calculated average retinal vascular calibers. Height, weight, body mass index (BMI) and three separate blood pressure measurements were taken and averaged.
On average, the children spent 1.9 hours per day in screen time and 36 minutes a day in total physical activity. Children in the highest levels of physical activity at just over an hour or more had significantly wider average retinal arteriolar caliber than those spending just under half an hour or less per day.
Increased screen time was associated with narrower average retinal arteriolar diameter after adjusting for age, sex, ethnicity, iris color, length of the eyeball, BMI, birth weight and blood pressure. Each hour per day of TV viewing time was associated on average with 1.53 microns narrower retinal arteriolar caliber.
"Excessive screen time leads to less physical activity, unhealthy dietary habits and weight gain," Gopinath said. "Replacing one hour a day of screen time with physical activity could be effective in buffering the effects of sedentariness on the retinal microvasculature in children. Free play should be promoted and schools should have a mandatory two hours a week in physical activity for children."
Physical activity enhances endothelial function and increases blood flow resulting in enhanced nitric oxide production, which has a positive effect on the linings of blood vessels.
The researchers said their findings might not be applicable to other regions of the world because of the temperate climate in Australia, where children are more apt to play outdoors. Study limitations included the use of parental rather than objective measurement of the children's time spent in physical and sedentary activities.
"Parents need to get their children up and moving and off the couch," Gopinath said. "Parents can also lead the way by being more physically active themselves."

**Source: American Heart Association